Introducing Reliable’s own Test and Drain valve: the Model TD. The valve is manufactured in the USA, FM Approved and UL Listed. The Model TD is a three-position ball valve with both a drain valve and an Inspectors Test connection in one unit. The valve is a multi-function device that permits easier and quicker installation, with fewer parts, leading to lower installation costs.
Test and Drain valves have three primary functions:
- To enable a sprinkler installation to be rapidly drained for routine and emergency maintenance.
- To facilitate the periodic testing of the system as required by design codes.
- To prevent an over-pressure condition within the system when incorporated with a pressure relief valve.
NFPA13 220.127.116.11 states that: ‘an alarm test connection not less than 1 in. (25mm) in diameter, terminating in a smooth bore corrosion resistant orifice, giving a flow equal to or less than one sprinkler of a type having the smallest K-factor installed on the system, shall be provided to test each waterflow alarm device for each system.’ The Reliable Model TD comes in sizes 1” (25mm), 1¼” (32mm) and 2” (50mm) to allow connection to different drain pipe sizes. It’s available in a wide range of K-factors to allow accurate representation of the flow of water from the sprinklers installed in the system and ensure that the alarm will trigger upon sprinkler operation. NFPA 13 requires that the K-factor of the test and drain valve is equal to or smaller than the smallest K-factor sprinkler installed on the system. Thus, a test and drain valve with a K-factor smaller than the smallest K-factor sprinkler installed on the system complies with NFPA 13.
The Reliable Model TD valve must be installed downstream of the floor control valve and connected to a drain riser. The Reliable Model TD valve is rated to 300psi (20.7 bar) to allow it to be installed on typical 175 psi (12 bar) sprinkler systems, as well as higher pressure sprinkler systems up to 300 psi (20.7 bar). The integral sight glass enables visual verification that water is flowing, negating the need to relocate and observe water flowing from the drain outlet, saving the installer time spent on maintenance as well as reducing the amount of water used during testing.
Temperature rises and the effects of gravity in tall buildings can easily cause system pressure to rise above the maximum rated system pressure. Pressure relief valves are automatic devices that slowly release water from the sprinkler system into a drain to prevent system over-pressurisation. NFPA13 Section 18.104.22.168 states that unless auxiliary air reservoirs are provided, ‘. . . a wet pipe system shall be provided with a listed relief valve not less than ½” (15mm) in size and set to operate at 175 psi (12 bar) or 10 psi (0.7 bar) in excess of the maximum system pressure, whichever is greater’. The Reliable Model TD is available with an optional pressure relief valve kit to also meet the NFPA 13 requirement for a relief valve. The relief valve kit is factory-set to release excess pressure at defined levels of: 175psi (12 bar), 185psi (13 bar), 210psi (14 bar), 260psi (18 bar) or 310psi (21 bar).
An optional locking mechanism fixes the valve in the closed position utilising a customer supplied padlock. This prevents accidental activation of the valve, where a person may inadvertently open the valve causing water to flow, triggering alarms. This tamper-resistant alternative is essential should the unit be located in public areas such as stairwells.
To run a test, simply rotate the handle counter clockwise until the ‘Test’ position is aligned and the ball detent. Further rotation of the handle to the ‘Drain’ position will allow for the system to be drained, then return the handle to the ‘Off’ position after completion. The Reliable Model TD valve with optional relief valve kit is a compact answer to three important requirements for wet pipe systems: drain, test, and pressure relief.
For more information, go to www.reliablesprinkler.com